1. Field of the Invention
The present invention relates to a farrier's tool and, more particularly, to a measuring tool operable for determining the break-over point of a horses hoof and to a method for preparing the hoof for shoeing.
2. Prior Art
Horses need periodic shoeing to protect their hooves and prevent damage to their feet. Typically, the wear and tear on the shoe and the normal growth and expansion of the hoof requires filing, trimming and reshoeing every six to eight weeks. In accordance with the prior art, prior to installing a horseshoe, the farrier first removes the old shoe then determines the flatness and the plane of the ground-contacting portion of the hoof. The farrier then makes corrections by peeling, cutting and/or filing to shape and flatten the bottom of the hoof. The width of the hoof is then measured and the correct horseshoe selected, shaped as required, and placed against the corrected bottom of the hoof and nailed to the hoofwall.
Errors in shoeing can lead to damage to the horse's leg and foot. The horse's feet and legs can become damaged if unnecessary strain is placed on components of the foot such as bones, tendons, ligaments and the like, which may cause the horse to go lame. The prior art method for preparing the hoof of a horse for shoeing pays particular attention to the lateral width and flatness of the foot. U.S. Pat. No. 4,813,148 discloses a device and method for determining the flatness of a horse's hoof and for making corrections therein. U.S. Pat. No. 5,996,698 discloses a farrier rasp that includes means for measuring the width of a horse's hoof at the same time the hoof is being filed and shaped for shoeing, thereby avoiding the necessity for the additional step of lifting the foot of the horse to measure it with a different instrument after filing.
Notwithstanding the importance of the flatness of the foot, the contour of the anterior (or forward) portion of the toe of the hoof is also important. A particular problem that may result from improper horseshoeing is injury to the coffin bone in the foot arising from pressure exerted by the hard, horny overlying hoofwall away from the coffin bone. When a horse lifts its hoof to walk, the heel leaves the ground first, temporarily transferring weight to the toe. The rising foot rotates around a transverse axis in the foot which is called the break-over axis. If the forward portion of the toe (or shoe) is flat, the weight transferred thereto creates a high torque which forces the hoofwall away from the coffin bone which can result in damage thereto. There is a need for a method for identifying the portion of the hoof forward of the break-over plane and tapering or beveling the forward edge of the lower, ground-contacting surface of the hoof such that the pressure exerted by the hoofwall and the coffin bone is evenly distributed over the interface therebetween, particularly when the horse is walking or running.